Is there life on Mars?
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NASA's Orion Spacecraft Launch
3. Is there life on Mars?
The answer is not as far as we know, but there might have been in the past and there might be again in the future. Mars is the planet we know of that's most likely to have had some kind of life at some point. The now dry 'rivers' and chasms tell us that at some point Mars might have had water on its surface, not dissimilar to our rivers, seas and lakes system. Picture: PA